The invention relates to shaping caps for dental pin structures as well as kits and processes for the preparation of dental pin structures.
Anchorage pins are used to secure tooth restorations and to reconstruct missing hard tooth substance. These are usually inserted into the root canal and therefore also called root pins. However, besides the intracanalicular anchorage, a parapulpal anchorage is also usual.
The insertion of these pins into the root canal takes place in three phases. In the first phase, the root canal is prepared up to the apex with customary root canal instruments. In the second phase, the coronal part of the root is prepared with standardized drills. In the third phase, the anchorage or root pin is inserted into the prepared canal.
A so-called pin or stump structure is then modelled on the anchorage pin. The structures can be built up directly in the mouth of the patient with moldable materials such as amalgam and composite and be ground into the correct shape. However, they can also be prepared indirectly in the dental laboratory using an impression of the prepared hard tooth substance with the set pin. Lastly, this structure is crowned or veneered.
To manufacture pin structures from composite materials, caps of flexible plastic material such as silicone or polyethylene can be used as auxiliaries which allow easy shaping of a standard stump. The cap is usually filled with composite, pushed over the root pin and the composite is then cured. The caps consist of soft, flexible material and after curing can be easily removed from the cured composite material. The stump structure is then worked on further. The caps are obtainable for front and back teeth in different sizes. The composites used to prepare the structures contain, besides a polymerizable matrix material, usually particulate fillers. The load-bearing capacity of the structures is limited.